Insulin resistance is a silent condition that increases the chances of developing type 2 diabetes. In insulin resistance condition the muscle, fat, and liver cells do not use insulin properly. The pancreas tries to keep up with the demand for insulin by producing more. Excess weight also contributes to insulin resistance because too much fat interferes with muscles' ability to use insulin. Lack of exercise further reduces muscles' ability to use insulin.
According to the American Diabetes Association, pre-diabetes can be defined as the state that occurs when a person's blood glucose levels are higher than normal but not high enough for a diagnosis of diabetes. About 11 percent of people with pre-diabetes in the Diabetes Prevention Program standard or control group developed type 2 diabetes each year during the average 3 years of follow-up. Other studies show that many people with pre-diabetes develop type 2 diabetes in 10 years.
Pre-diabetes was previously called Impaired Glucose Tolerance IGT and it has also been referred to as borderline or chemical diabetes. Insulin resistance and obesity linked to pre-diabetes can be an increased risk factor for hypertension, or high blood pressure which is one of the most important risk factors for cardiovascular disease, which can lead to a heart attack or stroke. If left untreated, hypertension can also lead to a wide variety of other life-threatening conditions, such as kidney damage and congestive heart failure.
People with pre-diabetes are, therefore, at higher risk of cardiovascular disease. People with pre-diabetes have a 1.5-fold risk of cardiovascular disease compared to people with normal blood glucose, whereas people with diabetes have a 2- to 4-fold increased risk of cardiovascular disease. Always according to the American Diabetes Association people with pre-diabetes can delay or prevent the onset of type 2 diabetes. This can be done through lifestyle changes.
An estimated 20 million people have pre-diabetes in the U.S. and this number is growing rapidly. 50 percent of the people who have pre-diabetes are likely to develop Type 2 diabetes.
Early diagnosis is important. In the early years of pre-diabetes or diabetes, the beta cells are progressively damaged by high blood sugars. Usually by the time diabetes is diagnosed, half of the beta cells are non-functional. This cannot be reversed so that the beta cells can go back to insulin production. However, when an early diagnosis of pre-diabetes is made, almost 100 percent of beta cells are functional. If lifestyle changes are made and some diabetes medications are used right away, many beta cells will stay healthy and make blood sugar control easier.
Diabetes or pre-diabetes can be detected and differentially diagnosed with one of the following tests:                Fasting Glucose Test, which measures blood glucose after not eating overnight. This test is most reliable when done in the morning. Fasting glucose levels of 100 to 125 mg/dL are above normal but not high enough to be called diabetes. This condition is called pre-diabetes or impaired fasting glucose (IFG), and it suggests that patient has probably had insulin resistance for some time. IFG is considered a pre-diabetic state, meaning that the patient is are more likely to develop diabetes but does not yet have it. Levels equal to or higher than 126 mg/dL are normally associated with diabetes.        Glucose Tolerance Test, which measures blood glucose after an overnight fast and 2 hours after patient drinks a sweet liquid provided by the doctor or laboratory. If patient blood glucose falls between 140 and 199 mg/dL, 2 hours after drinking the liquid, patient glucose tolerance is above normal but not high enough for diabetes. This condition, also a form of pre-diabetes, is called impaired glucose tolerance (IGT) and, like IFG, it points toward a history of insulin resistance and a risk for developing diabetes.        
Levels equal to or higher than 200 mg/dL are normally associated with diabetes.
If conventional tests show that patient has IFG or IGT, the doctor may suggest changes in diet and exercise to reduce the risk of developing diabetes.
Insulin resistance is elusive, perhaps more easily identified than measurable. The WHO classification of the metabolic syndrome includes insulin resistance, but only when measured by hyperinsulinaemic euglycaemic clamp (Insulin Sensitivity Evaluation test). Using this test only people in the lowest quartile are defined as having insulin resistance. The clamp requires bilateral cannulation, arterialisation of blood flow to the vein and 2 hours of measures. The mean rate of glucose infusion during the last 30 minutes of the clamp is considered the insulin sensitivity index (ISI). Diabetes is a widespread disease present throughout the world and is associated with major clinical complications including microvascular complications such as diabetic retinopathy, diabetic neuropathy and diabetic nephropathy, and macrovascular complications such as atherosclerosis, peripheral vasculopathies, obesity, hypertension myocardial infarction, stroke, polycystic ovary syndrome and syndrome X (J. Am. Osteopath. Assoc., 2000 October; 100(10):621-34; Jama, 2002 November, 27; 288(20):2579-88).
Said complications constitute a serious threat to the life and well-being of the individual.
Attempts to prevent the onset of type 2 diabetes have already been done. Researchers sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases conducted the Diabetes Prevention Program (DPP) to find the most effective ways to prevent or delay the onset of type 2 diabetes. Volunteers were recruited from groups known to be at particularly high risk for IGT and type 2 diabetes. The study was designed to compare the effectiveness of lifestyle changes (weight loss through exercise and diet) with drug therapy (metformin). A control group received a placebo and information on diet and exercise. Participants assigned to the intensive lifestyle intervention reduced their risk of getting type 2 diabetes by 58 percent over 3 years.
Participants treated with metformin reduced their risk by 31 percent.
Drugs used for many years, such as the biguanides and sulphonylurea, are available on the market for the treatment of type 2 diabetes. Many of these, such as, for example, metformin, present gastrointestinal disorders, danger of acidosis in conditions of renal, cardiac, hepatic, pulmonary insufficiency, etc., as side effects. The sulphonylureas have episodes of hypoglycaemia as their possible side effects. Drugs recently introduced onto the market are the thiazolidonides, whose side effects such as liver toxicity, increased LDL cholesterol, weight gain and oedema have given cause for concern.
In WO 99/01126 is described a combination of statin and alkanoyl L-carnitines useful for treating diseases due to an altered lipid metabolism.
In WO00/74675 is described the use of carnitines for reducing the toxicity due to the administration of statins.
In Clin. Ter. 1992 January; 140(1 Pt 2):17-22 is described the hypotriglyceridemic action of L-carnitine in combination with simvastatin, in patient with renal failure.
In Atherosclerosis 188, 2006, 455-461 is described the efficacy of L-carnitine in combination with simvastatin in lowering Lipoprotein(a), in patient with type 2 diabetes.
In Minerva Medica, Vol. 80, N° 3 is described the use of L-carnitine for the treatment of hypertension in patient with type 2 diabetes. WO 98/01128 discloses the use of the acetyl L-carnitine, isovaleryl L-carnitine, propionyl L-carnitine to increase the levels of IGF-1. Diabetes is also included in the long list of curable pathologies reported in WO 98/01128.
WO 98/41113 describes a therapeutic nutritive composition for patients with diabetes mellitus consisting of gamma linoleic acid, acetyl L-carnitine, mineral salts and vitamins.
U.S. Pat. No. 4,362,719 describes the use of the L-carnitine and the acyl L-carnitine in treating the juvenile onset diabetes mellitus.
U.S. Pat. No. 5,430,065 describes the use of the L-carnitine and the acyl L-carnitine in the long-term treatment of those patients with non insulin-dependent diabetes.
In Journal of Cellular Physiology 203; 2005; 439-446 is reported that the addition of acetyl L-carnitine to the culture medium dramatically affected the ability of myocytes to respond to insulin treatment.
In these documents it is never mentioned the use of acetyl L-carnitine in combination with anti hypertensive drug for the prevention or delay of onset of type 2 diabetes and its clinical complications in pre-diabetic subjects.
Ever increasing attention is being devoted to the so-called risk factors recognised as underlying these diseases, and there is still a perceived need for a medicine capable of acting on the various sources of this pathological picture, without, at the same time, being associated with severe side effects, which, as in the case of certain antidiabetic drugs, may even make it necessary to discontinue the therapy.